1. Field of the Invention
The exemplary embodiments relate to a method and apparatus for encoding and decoding a residual signal, and more particularly, to a method and apparatus for coding a residual signal by using a masking curve that is generated from an audio signal.
2. Description of the Related Art
In general, in order to encode a multi-channel audio signal, the multi-channel audio signal is downmixed to generate a mono or stereo signal, and the mono or stereo signal is transmitted to a decoding apparatus. However, when the decoding apparatus upmixes the downmixed audio signal, a difference signal is generated between the multi-channel audio signal and the upmixed audio signal.
In order to prevent generation of the difference signal, when an audio signal encoding apparatus encodes the multi-channel audio signal, the audio signal encoding apparatus performs encoding on the difference signal and then transmits the difference signal to the decoding apparatus. The audio signal encoding apparatus divides the difference signal into a plurality of sub-bands, obtains an average energy in each sub-band, decodes the average energy, and thus encodes the difference signal.